1. Field of the Invention
This invention relates broadly to grenade launcher attachments for gas-operated automatic and semi-automatic rifles. More particularly, it concerns improved trigger assemblies for the grenade launcher attachments.
2. Description of the Prior Art
Grenade launchers for attachment to gas-operated service rifles and carbines such as the M16 and M4 are known firearms devices, e.g. see U.S. Pat. Nos. 3,641,145 and 6,281,145. A need exists for such launchers to have a trigger assembly that allows the operator to deliver repeated hammer strikes to the primer of the loaded cartridge without having to open the breach to reset the hammer. The state of the art in grenade launchers is the M203 that has a firing mechanism that is cocked when the weapon is locked shut. It can only be released to strike the primer of the loaded cartridge one time without opening the breach and closing it again thereby resetting the hammer.
There have been many double-acting trigger assemblies for firearms previously designed that allow trigger pull to cock and trip the hammer repeatedly, e.g., see U.S. Pat. Nos. 3,965,603; 4,285,152; 5,160,795 and 5,400,537.
It has also been known to construct trigger assemblies for firearms wherein an increased pressure is required at the end of the trigger stroke to provide a clear tactile indication to the shooter that the hammer is in pending release to fire the weapon, e.g. see U.S. Pat. Nos. 4,974,356 and 6,571,502.
The present invention provides further improvements in the construction of grenade launchers for attachment to rifles and their trigger assemblies.